The patch titled
fault-injection capability for kmalloc
has been added to the -mm tree. Its filename is
fault-injection-capability-for-kmalloc.patch
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
------------------------------------------------------
Subject: fault-injection capability for kmalloc
From: Akinobu Mita <akinobu.mita@xxxxxxxxx>
This patch provides fault-injection capability for kmalloc.
Boot option:
failslab=<interval>,<probability>,<space>,<times>
<interval> -- specifies the interval of failures.
<probability> -- specifies how often it should fail in percent.
<space> -- specifies the size of free space where memory can be
allocated safely in bytes.
<times> -- specifies how many times failures may happen at most.
Debugfs:
/debug/failslab/interval
/debug/failslab/probability
/debug/failslab/specifies
/debug/failslab/times
/debug/failslab/ignore-gfp-highmem
/debug/failslab/ignore-gfp-wait
Example:
failslab=10,100,0,-1
slab allocation (kmalloc(), kmem_cache_alloc(),..) fails once per 10 times.
Cc: Pekka Enberg <penberg@xxxxxxxxxxxxxx>
Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxx>
---
lib/Kconfig.debug | 7 +++
mm/slab.c | 90 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 97 insertions(+)
diff -puN lib/Kconfig.debug~fault-injection-capability-for-kmalloc lib/Kconfig.debug
--- a/lib/Kconfig.debug~fault-injection-capability-for-kmalloc
+++ a/lib/Kconfig.debug
@@ -418,6 +418,13 @@ config LKDTM
config FAULT_INJECTION
bool
+config FAILSLAB
+ bool "Fault-injection capabilitiy for kmalloc"
+ depends on DEBUG_KERNEL
+ select FAULT_INJECTION
+ help
+ This option provides fault-injection capabilitiy for kmalloc.
+
config FAULT_INJECTION_DEBUG_FS
bool "Debugfs entries for fault-injection capabilities"
depends on FAULT_INJECTION && SYSFS
diff -puN mm/slab.c~fault-injection-capability-for-kmalloc mm/slab.c
--- a/mm/slab.c~fault-injection-capability-for-kmalloc
+++ a/mm/slab.c
@@ -108,6 +108,7 @@
#include <linux/mutex.h>
#include <linux/rtmutex.h>
#include <linux/uaccess.h>
+#include <linux/fault-inject.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
@@ -3094,12 +3095,101 @@ static void *cache_alloc_debugcheck_afte
#define cache_alloc_debugcheck_after(a,b,objp,d) (objp)
#endif
+#ifdef CONFIG_FAILSLAB
+
+static struct failslab_attr {
+
+ struct fault_attr attr;
+
+ u32 ignore_gfp_highmem;
+ u32 ignore_gfp_wait;
+
+#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
+
+ struct dentry *ignore_gfp_highmem_file;
+ struct dentry *ignore_gfp_wait_file;
+
+#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
+
+} failslab = {
+ .attr = FAULT_ATTR_INITIALIZER,
+};
+
+static int __init setup_failslab(char *str)
+{
+ return setup_fault_attr(&failslab.attr, str);
+}
+__setup("failslab=", setup_failslab);
+
+static int should_failslab(struct kmem_cache *cachep, gfp_t flags)
+{
+ if (cachep == &cache_cache)
+ return 0;
+ if (flags & __GFP_NOFAIL)
+ return 0;
+ if (failslab.ignore_gfp_highmem && (flags & __GFP_HIGHMEM))
+ return 0;
+ if (failslab.ignore_gfp_wait && (flags & __GFP_WAIT))
+ return 0;
+
+ return should_fail(&failslab.attr, obj_size(cachep));
+}
+
+#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
+
+static int __init failslab_debugfs(void)
+{
+ mode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
+ struct dentry *dir;
+ int err;
+
+ err = init_fault_attr_dentries(&failslab.attr, "failslab");
+ if (err)
+ return err;
+ dir = failslab.attr.dentries.dir;
+
+ failslab.ignore_gfp_wait_file =
+ debugfs_create_bool("ignore-gfp-wait", mode, dir,
+ &failslab.ignore_gfp_wait);
+
+ failslab.ignore_gfp_highmem_file =
+ debugfs_create_bool("ignore-gfp-highmem", mode, dir,
+ &failslab.ignore_gfp_highmem);
+
+ if (!failslab.ignore_gfp_wait_file ||
+ !failslab.ignore_gfp_highmem_file) {
+ err = -ENOMEM;
+ debugfs_remove(failslab.ignore_gfp_wait_file);
+ debugfs_remove(failslab.ignore_gfp_highmem_file);
+ cleanup_fault_attr_dentries(&failslab.attr);
+ }
+
+ return err;
+}
+
+late_initcall(failslab_debugfs);
+
+#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
+
+#else /* CONFIG_FAILSLAB */
+
+static inline int should_failslab(struct kmem_cache *cachep, gfp_t flags)
+{
+ return 0;
+}
+
+#endif /* CONFIG_FAILSLAB */
+
static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags)
{
void *objp;
struct array_cache *ac;
check_irq_off();
+
+ if (should_failslab(cachep, flags))
+ return NULL;
+
ac = cpu_cache_get(cachep);
if (likely(ac->avail)) {
STATS_INC_ALLOCHIT(cachep);
_
Patches currently in -mm which might be from akinobu.mita@xxxxxxxxx are
acpi-fix-single-linked-list-manipulation.patch
debugfs-check-return-value-correctly.patch
git-input.patch
git-mtd.patch
gss_spkm3-fix-error-handling-in-module-init.patch
auth_gss-unregister-gss_domain-when-unloading-module.patch
auth_gss-unregister-gss_domain-when-unloading-module-fix.patch
git-pcmcia.patch
pci-fix-__pci_register_driver-error-handling.patch
acpiphp-fix-missing-acpiphp_glue_exit.patch
acpiphp-fix-use-of-list_for_each-macro.patch
git-watchdog.patch
paride-return-proper-error-code.patch
bit-revese-library.patch
crc32-replace-bitreverse-by-bitrev32.patch
video-use-bitrev8.patch
net-use-bitrev8.patch
isdn-hisax-use-bitrev8.patch
atm-ambassador-use-bitrev8.patch
isdn-gigaset-use-bitrev8.patch
isdn-fix-missing-unregister_capi_driver.patch
fault-injection-documentation-and-scripts.patch
fault-injection-capabilities-infrastructure.patch
fault-injection-capabilities-infrastructure-tidy.patch
fault-injection-capabilities-infrastructure-tweaks.patch
fault-injection-capability-for-kmalloc.patch
fault-injection-capability-for-alloc_pages.patch
fault-injection-capability-for-disk-io.patch
fault-injection-process-filtering-for-fault-injection-capabilities.patch
fault-injection-stacktrace-filtering.patch
fault-injection-Kconfig-cleanup.patch
-
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
